Monolithic Silicon Photomultiplier Array

Abstract

An optical system may include a substrate and a plurality of silicon photomultipliers (SiPMs) monolithically integrated with the substrate. Each SiPM may include a plurality of single photon avalanche diodes (SPADs). The optical system also includes an aperture array having a plurality of apertures. The plurality of SiPMs and the aperture array are aligned so as to define a plurality of receiver channels. Each receiver channel includes a respective SiPM of the plurality of SiPMs optically coupled to a respective aperture of the plurality of apertures.

1 - 20 . (canceled) 
     
     
         21 . An optical system comprising:
 a substrate having a first surface and a second surface opposite the first surface;   a plurality of light-detecting elements monolithically integrated with the first surface of the substrate, wherein each light-detecting element comprises a plurality of detectors; and   a set of optical waveguides, wherein each of the optical waveguides is configured to couple light into a respective light-detecting element of the plurality of light-detecting elements.   
     
     
         22 . The optical system of  claim 21 , wherein each optical waveguide extends vertically from the first surface of the substrate. 
     
     
         23 . The optical system of  claim 21 , wherein the optical waveguide has a tapered shape. 
     
     
         24 . The optical system of  claim 21 , wherein the optical waveguide has a straight sidewall. 
     
     
         25 . The optical system of  claim 21 , wherein each light-detecting element comprises a dielectric stack over the light-detecting element. 
     
     
         26 . The optical system of  claim 21 , wherein each light-detecting element of the plurality of light-detecting elements comprises a silicon photomultiplier (SiPM) device. 
     
     
         27 . The optical system of  claim 26 , wherein each SiPM comprises a plurality of single photon avalanche diodes (SPADs). 
     
     
         28 . The optical system of  claim 21 , wherein the plurality of light-detecting elements are arranged along the substrate in a hexagonal or square array. 
     
     
         29 . The optical system of  claim 21 , further comprising:
 an aperture array comprising a plurality of apertures, wherein the plurality of light-detecting elements and the aperture array are aligned so as to define a plurality of receiver channels, wherein each receiver channel comprises a respective light-detecting element of the plurality of light-detecting elements optically coupled to a respective aperture of the plurality of apertures; and   a baffle structure, wherein the baffle structure comprises a plurality of openings in an optically opaque material, wherein the baffle structure is arranged between the aperture array and the plurality of light-detecting elements such that each receiver channel comprises a respective light-detecting element of the plurality of light-detecting elements optically coupled to a respective aperture of the plurality of apertures via a respective opening in the baffle structure.   
     
     
         30 . The optical system of  claim 21 , further comprising a thick opaque plate, wherein the thick opaque plate comprises a plurality of deep holes, and wherein each deep hole aligns with a respective light-detecting element. 
     
     
         31 . The optical system of  claim 21 , further comprising a plurality of electrical conductors, wherein the plurality of electrical conductors are coupled to the plurality of light-detecting elements via at least one of: a through substrate via (TSV) or a side routing arrangement. 
     
     
         32 . The optical system of  claim 31 , further comprising at least one electrical conductor coupled to the second surface of the substrate. 
     
     
         33 . The optical system of  claim 21 , further comprising at least one isolation trench in the substrate, wherein the at least one isolation trench is arranged between neighboring light-detecting elements. 
     
     
         34 . The optical system of  claim 33 , wherein the at least one isolation trench is at least partially filled with at least one of: a metal material, an optically-opaque material, a conductive material, or a non-conductive material. 
     
     
         35 . The optical system of  claim 33 , wherein the at least one isolation trench provides electrical isolation or optical isolation between the neighboring light-detecting elements. 
     
     
         36 . The optical system of  claim 21 , further comprising a reflective grid patterned along a top surface of each light-detecting element, wherein the reflective grid optically isolates the light-detecting element from neighboring light-detecting elements. 
     
     
         37 . A device comprising:
 a series of optical substrates, wherein each optical substrate comprises:
 a plurality of light-detecting elements monolithically integrated with the optical substrate, wherein each light-detecting element fills a respective circular area on the optical substrate, wherein each light-detecting element comprises a plurality of detectors, and wherein each light-detecting element is arranged in a hexagonal or square array on the substrate; and 
 an isolation component configured to optically isolate or electrically isolate each light-detecting element from neighbouring light-detecting elements. 
   
     
     
         38 . The device of  claim 37 , wherein the isolation component comprises an at least one isolation trench in the substrate, wherein the at least one isolation trench is arranged between neighboring light-detecting elements. 
     
     
         39 . The device of  claim 37 , wherein each optical substrate further comprises a set of optical waveguides, wherein each of the optical waveguides is configured to couple light into a respective light-detecting element of the plurality of light-detecting elements. 
     
     
         40 . The device of  claim 39 , further comprising:
 an aperture array comprising a plurality of apertures, wherein the plurality of light-detecting elements and the aperture array are aligned so as to define a plurality of receiver channels, wherein each receiver channel comprises a respective light-detecting element of the plurality of light-detecting elements optically coupled to a respective aperture of the plurality of apertures; and   a baffle structure, wherein the baffle structure comprises a plurality of openings in an optically opaque material, wherein the baffle structure is arranged between the aperture array and the plurality of light-detecting elements such that each receiver channel comprises a respective light-detecting element of the plurality of light-detecting elements optically coupled to a respective aperture of the plurality of apertures via a respective opening in the baffle structure.